Small scale and multi-pixel are demanded to a solid-state imaging sensor. Therefore, reduction of pixels is developed. However, with the reduction of pixels, the sensitivity deteriorates, and thus it is demanded to compensate for the deterioration of sensitivity due to the reduction of an aperture ratio, and improve the sensitivity. In the solid-state imaging sensor, incident light is reflected on the surface of a Si substrate. Therefore, the intensity of light that reaches a light receiving portion is lost, and the sensitivity deteriorates, and the incident light from an unexpected light path causes flare and ghosts.
Accordingly, such a technology is proposed to effectively suppress the reflection of incident light on all wavelength regions (all visible light) of the incident light on a light receiving portion by forming a reflection preventing layer having a concavo-convex structure (also referred to as a moth-eye structure) corresponding to a wavelength region of incident light on the light receiving portion (refer to, e.g., Patent Literature 1).